Installation help with Alpine IVAD-106 headunit

Hi, I have just bought the above headunit from the US (brand-new), I live in Hungary (Europe). I also bought the Alpine KCE-300BT module for my mobile and I still had the rear camera from the previous model of Alpine, IVAD-105 (my car was broken and the headunit stolen).
Well, after the installation the Ipod and the radio seem to work properly but no picture of DVD (just sound), no rear camera picture, missing menu titles (no general setup) and freezing the whole thing when receiving incoming calls or want to call somebody. In such cases I have to pull out the key and start the engine again to get life in it.
I am absolutely sure that the headunit is OK but something must be done wrong at the beginning as there are so many things, which do not work.